Kaufman does a nice job of showing a formula to isolate the variables that lead to earning a billion dollars by looking at after-tax profits generated by customers, the number of customers served and a person's share of ownership in a company. However, his formula significantly over-states what would be required to become a billionaire because he only takes into consideration a business' earnings, not the value generated by those earnings. In fairness to Kaufman he does describe, in an oblique way, how the stock market may value those earnings.

I know the purpose of his formula isn't to figure out how quickly someone could become a billionaire, but rather the level of profitability of customers over time and the number of customers served, to determine what would be required to earn a billion dollars. However, under his formula, if you were earning, on average, $50 million a year it would take you 20 years to earn a billion dollars. While this is all theoretical because no business starts out earning $50 million a year, if a business would sell for 15x earnings then $50 million in earnings would represent a business value of $750 million. So, rather than it taking 20 years of $50 million in earnings, it would really only require 5 years of earnings plus the value of those earnings to total $1 billion.

OK, now that we've cleared that up all you need to do is figure out how to generate $50 million a year in earnings and in five years you can be yachting in the Mediterranean.